Re: [PATCH v2 0/3] fetch the alignment of device dax

[Liu, Jingqi]

Ping for comments.

Hi Paolo, Dan, Joao,
Any comments for this series.

Thanks,
Jingqi

On 4/15/2020 11:35 AM, Liu, Jingqi wrote:
> This series adds libdaxctl support and fetchs the alignment of
> device dax through libdaxctl [1] APIs.
>
> QEMU uses mmap(2) to maps vNVDIMM backends and aligns the mapping
> address to the page size (getpagesize(2)) by default. However, some
> types of backends may require an alignment different than the page
> size. The 'align' option is provided to memory-backend-file to allow
> users to specify the proper alignment.
>
> For device dax (e.g., /dev/dax0.0), the 'align' option needs to
> match the alignment requirement of the device dax, which can be fetched
> through the libdaxctl APIs.
>
> [1] Libdaxctl is a part of ndctl project.
> The project's repository is: https://github.com/pmem/ndctl
>
> Changelog:
>    v2: Per Paolo and Dan suggestions, fetch the alignment of device dax
>        through libdaxctl APIs.
>
>    v1: The initial version.
>        Fetch the alignment through "/sys/dev/char/%d:%d/device/align".
>
> Jingqi Liu (3):
>    exec: fetch the alignment of Linux devdax pmem character device nodes
>    docs/nvdimm: add description of alignment requirement of device dax
>    configure: add libdaxctl support
>
>   configure       | 30 +++++++++++++++++++++++++++
>   docs/nvdimm.txt |  9 +++++++++
>   exec.c          | 54 ++++++++++++++++++++++++++++++++++++++++++++++++-
>   3 files changed, 92 insertions(+), 1 deletion(-)